Josh,
Your FedEx account rep can make this process happen for you (or not, as some people have experienced). If you have not spoken with YOUR rep (as opposed to the countless, random phone people that really don't care), that should be your priority. If you have, and have been getting the run around, ask for a new rep.
I had a tough time making initial contact with my rep, so I sent an email to:
Lenny Evansek
FedEx Account Executive
leonard.evansek@fedex.com
and he got things rolling - my rep called me that same day, and the process was underway.